posted by Sierra Marquina -

According to reports, guests can only use the loo at certain times and are not allowed to bring phones, gifts or swords. Yes, swords.

They are, however, encouraged to wear hats in the lengthy “critical guidance” and will have to undergo a security test three miles away at the Windsor Farm Shop where they will then take either the “green route” or “red route” to make their way to St. George's Chapel.

Meghan’s wedding dress also has its own set of rules: It should have lace, bare no cleavage, cover her shoulders and potentially include a tiara. The Queen also gets final approval of the design.

Guests also, of course, should avoid white and can’t wear any medals. According to CNN Royal Commentator Victoria Arbiter guests will likely dress in spring colors and prints.

"British weddings in general all follow all kind of the same rules when it comes to weddings and it's very much a brightly colored, garden party type of event, so day dresses with shoulders covered in the chapel is the way to go," Arbiter told Us Weekly. "I think you'll see the ladies in lots of floral prints, lots of bright colors and men in a morning suit [a formal set of clothes including a long black or grey coat, striped trousers, and a top hat] if they're not in the military."

Among those invited are celebs including the Spice Girls and also a bevy of commoners — 2,640 to be exact. As previously reported, Kensington Palace explained that Meghan and Prince Harry want the public to be involved.

"This wedding, like all weddings, will be a moment of fun and joy that will reflect the characters and values of the bride and groom," a spokesperson for Kensington Palace said back in March, explaining that "the couple has asked that the people chosen are from a broad range of backgrounds and ages, including young people who have shown strong leadership, and those who have served their communities.”

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